Existing core facilities for Oligonucleotide synthesis and for DNA Sequencing will be further supported by funds from the Research Center in Oral Biology, in order to obtain expedited services for members of the RCOB. All of the projects have a need for oligonucleotides, especially for PCR amplification and quantitation. In addition, Project 5 will require large quantities of anti-sense oligonucleotides for gene expression experiments. Project 6 will require oligonucleotides for DNA sequencing of PCR amplified DNAs or of mutants created by site-directed mutagenesis. All of the projects will have access to computer programs and to nucleotide and protein databases for analysis of DNA and protein sequences. The Oligonucleotide Synthesis Core Facility operates an Applied Biosystems Model 394 four column DNA synthesizer and provides custom synthesized oligonucleotides for DNA sequencing, PCR amplification, and site-directed mutagenesis. Charges for synthesis are kept as low as possible and are designed to recover only the reagent costs. Oligonucleotides are generally available with 24 to 48 hours of synthesis; additional purification by HPLC is available at no extra charge and adds approximately 1 to 2 days to the time required for delivery of the product. The DNA Sequencing Core Facility operates on Applied biosystems Model 373A automated DNA sequencer and a Perkin-Elmer Model 9600 Thermocycler. In addition, this core facility provides access to computer programs for analysis of DNA and protein sequences; these programs are leased on a yearly basis from the Genetics Computer Group, Inc. In addition, GENBANK and EMBL nucleotide sequence databases and Swiss-prot and NBRF protein databases are provided; the information in these resources are updated on a quarterly basis.